%I #17 Jan 22 2018 02:40:52
%S 0,1,-1,6,-18,115,-615,4732,-36148,337797,-3315645,37027826,
%T -440999526,5768129783,-80507865347,1210608394920,-19345811001000,
%U 329208442723465,-5922785067664185,112578608999452894,-2251115252850724090
%N Expansion of e.g.f. sinh(log(1+x))/cos(x).
%H G. C. Greubel, <a href="/A009576/b009576.txt">Table of n, a(n) for n = 0..448</a>
%F a(n) ~ n! * (-1)^(n+1) / (2*cos(1)). - _Vaclav Kotesovec_, Jan 23 2015
%t CoefficientList[Series[(x*(2 + x)*Sec[x])/(2*(1 + x)), {x, 0, 20}], x] * Range[0, 20]! (* _Vaclav Kotesovec_, Jan 23 2015 *)
%t With[{nmax = 50}, CoefficientList[Series[Sinh[Log[1 + x]]/Cos[x], {x, 0, nmax}], x]*Range[0, nmax]!] (* _G. C. Greubel_, Jan 21 208 *)
%o (PARI) x='x+O('x^30); concat([0], Vec(serlaplace(sinh(log(1+x))/cos(x)))) \\ _G. C. Greubel_, Jan 21 2018
%K sign,easy
%O 0,4
%A _R. H. Hardin_
%E Extended with signs by _Olivier GĂ©rard_, Mar 15 1997
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